瓶(píng) - bottle; measure word for bottles in Mandarin

瓶 (píng) is a bottle. Add 子 (zi) and 瓶子 (píngzi) is the ordinary word for the object sitting on a shelf; the bare character 瓶 (píng) is what actually does the counting work.

Like English "a bottle of water", 瓶 (píng) sits straight after the number: 一瓶水 (yì píng shuǐ), "a bottle of water", 一瓶啤酒 (yì píng píjiǔ), "a bottle of beer". Anything sold or served in a bottle, from fizzy drinks to shampoo, gets counted this way rather than with the generic 个 (gè).

Watch the tone. 瓶 (píng) is second tone, rising, easy to flatten into first tone if you are not listening for it - and a flat first tone nudges it toward 平 (píng), "flat, level", a completely different word that happens to share the same pinyin syllable.